Phonograph reproducer



R. C. MATHES.

PHONOGRAPH REPRODUCER.

APPLICATION FILED DEc.2,192o.

PIIIenIeIIv Mar. I4, 1922.

I l llII-lllllllllllllllHllllll I I I I I Il IIIIIIIHIIIII HIHHIII UNITED STATES PATENT oFFICE.

ROBERT C. MATHES, OF NEW YORK,.N. Y., ASSIGNOR T0 WESTERN ELECTRIC COM- l PANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION 0`F NEW YORK.

PHONOGRAPII REPRODUCER.

Specification of Letters Patent.

To all whom t may concern:

Be it known that I, ROBERT CARL MATHES, a citizen of the United States of America. residing :at New York, .in` the county of Bronx and State of New York, have invented certain new and useful Improvements in Phonograph Reproducers, of which the following is a full, clear, concise, and exact description.

This invent-ion relates to a volume of tone control Jfor a phonograph or gramophone.

Prior to this invention,l the common methods for changing the volume of tone consisted in constricting the cross sectional area of a horn at some point by means of shutters or valves. The inevitable result of such methods was to alter the reproducing characteristics.

vAn object of this invention is to produce a simple means of changing the loudness of reproduction without altering the acoustic properties of the system.

Another object is to produce a device by which the volume of tone may be altered while the machine is in operation.

In combination with a sound box and stylus lever, we have a sound modifier which consists of a support arm having a-slideway therein, attached to the sound box. A slide is mounted in said slideway and has an arm slidably connecting it with the stylus lever thus forming an adjustable fulcrum point `for the stylus lever. A set screw or other clamping means is used to retain the slide in any desired position.

The construction of the device will be more clearly understood from the following specifications and accompanying drawings of which Fig. 1 isa side elevation and 2 is a cross section of the device.

Like numbers refer to like members in both figures. The number 1 represents the 'Patented Mar. 14, 1922.

usual swinging arm of a machine carrying a sound box 2. Stylus lever 5 is attached to diaphragm 3 off the sound box 2 at point 4. Needle-6 is carried by the stylus lever 5. Support arm 8 is rigidly connected to the sound box by screws 9 and extends parallel to the stylus lever 5. A slidaway 10 is provided in the support arm and slide 11 is mounted in this slideway. This slide 11 is retained in any desired position by means of screw 12 which tightens members 15 and 16 of the slide 11 on the sides of the slideway 10. Arm 13 which is slidably connected with stylus lever 5 and is rigidly connected to slide 11 by means of screws 14, forms a fulcrum point at 7 for the stylus lever 5 carrying the needle 6.V

What is claimed is:

1. In combination with a sound box including a stylus lever, a sound modifier comprising a support arm attached to said sound box, a slide mounted on said support,

said slide carrying a. pivot point for said stylus lever. 2. In combination with a sound box including a stylus lever, a sound modifier comprising a support attached to the sound box,

a pivot point for the stylus lever carried by the support, and means for adjusting said pivot point to vary the ratio between Alengths of the stylus lever on opposite sides of the pivot point.

In witness whereof, I hereunto subscribe my name this 17 day of Nov. A. D., 1920;

ROBERTO. MATHEs. 

